Iridium vs. Platinum Plugs

[Afboy143]

http://advanceautoparts.com/english/youcan/html/pht/pht20010101ds.html

After reading the above site, it got me thinking about switching my autolite double plats to iridium plugs. Anyone try them? Stories of your own?

 

[JDraper]

I've got Iridium's in my Mach and they work very well. However, I wouldn't swap out the platinums until they are worn out. The platinums work just fine for most vehicles.

 

[Jefe]

I'm running Iridiums in my Focus just 'cause. Can't say I noticed any difference, and have heard that it is questionable as to their length of life that Denso states (200,000 miles). Also be VERY careful if you regap them as the center electrode is tiny.

I think the real advantage to them is they work well in turbo/supercharged aplications, as well as with nitrous, so you can run these rather than a copper plug.

 

[410Fortune]

you are not supossed to gap them or be VERY careful, you can knock the irridium right off (same with plat)
I ran NGK Irridium in my 5.0L in the BII, I took them out and went back to plat after 1 year I had a stumble at idle...it was the plugs. I dont think they do well at high altitude with 85-87 octane in the V8, I am going back to OEM plugs.

 

[tnmk]

I have the NGK iridiums in my PT Cruiser. I swapped 'cause the factory plugs and wires are junk. In fact there is a TSB to re-gap the factory plugs from .052 down to .040. With the iridiums (came gapped at .052) and new Crane Firewires (not available for our trucks that I've found) the idle and mpg got noticebly better and I didn't think I had a bad idle to begin with.

Plugs are tricky business. What works for some engines won't for another. I'd like to try the iridiums in my truck, but at $7.00 a pop x 8 I'm not sure. I can get Platinums for $3.00.

I'm edging toward Platinums with indexing washers.

 

[DCExplorer]

I just put in Autolite XP Iridiums and a set of Motorcraft wires. Plugs work great. Of course I don't have anything to compare it against except the old plugs that came out. However, the X now runs much better with the new plugs and wires. No problems so far.

 

[tnmk]

well I'mglad to hear that since I have the same motor.

 

[Afboy143]

Hmm interesting

I hear the argument about some plugs are better in some motors than others. I had the Bosch plats in there and when I went to Autolite Double Plats I could tell a world of difference. Maybe when the double plats need to be changed ill go Autolite Iridium.

 

[wpurple]

I swapped out the platnums for NGK coppers in my 99 mounty 5L , and the coppers seem to run better, although I run a blown application.

$1.75 a plug can't beat it. Only takes but a 1/2 hour to change them anyways.

 

[CDW6212R]

In general spark plugs are about the same, they work right or they don't. Most problems with plugs comes from there being something wrong with the old plugs, or damage while installing them.

The plug tip material does affect life, but do know that the longer the material lasts, the poorer of an electrical conductor it is.

Aluminum is the best plug tip material, and Beru does make them, called Silverstones, at about $6 per. I have them in my Mountaineer 302, I figured that I would try "the best." I noticed no difference, and I had no problem before then.

Either choose a basically stock plug, or what others have discovered. But know that most opinions will be based on some perceived problem with some plug. It usually comes from some worn out plugs being compared to brand new(any brand) plugs. Brand new plugs can be defective, myself and friends have experienced it.

Bottom line, the factory plugs are very good, Motorcraft makes good spark plugs. If you can take good care of your vehicle, then buy single platinums, not double. Don't wait 100,000 miles to change plugs, it's cheap and easy, and saves fuel($). Good luck,

 

[tnmk]

In general spark plugs are about the same, they work right or they don't. Most problems with plugs comes from there being something wrong with the old plugs, or damage while installing them.

The plug tip material does affect life, but do know that the longer the material lasts, the poorer of an electrical conductor it is.

QUOTE]

I don't think I can agree with this. If this were true then I wouldn't have seen any difference on my PT Cruiser. The factory Platinums came out at only 10,000 miles and replaced with Iridiums. And it runs ALOT better. This is a problem in all the PT's, not just mine. In fact the factory tells you to re-gap the originals down to .040 to make them work better. I didn't have to do that with the iridiums.

I've also seen a dyno test that shows small HP gains from one plug to another.

 

[Aussie Explorer]

I am Running NGK Iridium’s and NGK Leads on the 4.0 SOHC with no issues.

 

[Papa]

Ok so how much does this change in resistance for each of these plugs affect the inductive kick utilized by the coil packs in an X. It has been my understanding that this inductive kick is a major design component and can adversely affected by plugs and wires. Does anyone have any numbers on this? My personal experience is that new carbon wires run about 1500 ohms of resistance and when the resistance gets up to 7000 ohms they run like crap.

 

[CDW6212R]

Wire performance is not measureable by an ohm meter, that is a massive falicy.

The electrical charge does not travel through the wire core, yet that is what an ohm meter measures. The charge travels around the core, that's the purpose of the spiral windings. I may not be expressing the idea with the exact proper terms, but I read this on the Magnacor website. One of the biggest jobs of plug wires is to contain the magnetic interference produced by the signal.

Too much interference affects much more than radio reception. Bad wires can cause electrical problems with the other engine operating system, yet the wires could pass a resistance test.

Check out the Magnacor.com website if anyone is truly interested in maximum ignition performance. Regards,